Wind Pump Research Articles

Optimization of large-scale wind-powered centrifugal pumps

A study on the optimal matching of centrifugal pumps and large-scale wind turbines is reported. The study includes mathematical modelling of the performance of high-capacity centrifugal pumps when matched with efficient high-speed low-solidity wind turbines. The dependence of the performance of wind pumps on the dimensionless parameter v/√( gh), termed the wind pump’s Froude number, was fully analysed. Similar to earlier reported results on wind-powered piston pumps, analysis is showing that the wind pump’s Froude number is the dominant independent dimensionless parameter that fully defines the system’s performance. Operation with continuous variable transmission was analysed and shown to optimize the wind pump’s performance, particularly at medium and low wind speeds. The optimum relation between the required gearbox transmission ratio and Froude number of a wind-powered centrifugal pump was analytically established for three different pumps. In addition to continuous variable transmission operation, the analysis helps in optimally sizing constant transmission ratio systems.

Experimental and Numerical Investigation on Flow Characteristics of Large Cross-Sectional Ionic Wind Pump With Multiple Needles-to-Mesh Electrode

Ionic wind pumps have attracted considerable interest because of their low energy consumption, compact structures, flexible designs, and lack of moving parts. However, large cross-sectional ionic wind pumps have yet to be numerically analyzed and experimentally optimized. Accordingly, this study develops a large cross-sectional ionic wind pump with multiple needles-to-mesh electrode, as well as analyzes its flow characteristics using a proposed full three-dimensional simulation method validated with experimental data. To obtain a considerably high outlet average velocity, experimental studies and numerical methods are employed to optimize the pump's configuration parameters, including needle electrode configuration, needle diameter, grid size, and gap between electrodes. The breakdown voltage and highest velocity corresponding to the breakdown voltage increase with an increase in the needle tip-to-mesh gap. After parametric optimization, a maximum velocity of 2.55 m/s and a flow rate of 2868 L/min are achieved.

Prospect of Wind Energy as a Resource for Water Pumping in Ngaoundere

The modelling of wind energy conversion systems is of great importance if one intends to develop water pumping applications for a sustainable development. This study presents a technical assessment based on the measured wind data in which we investigate the possibility of coupling piston pump, roto-dynamic pump and electric pump with wind rotors for water pumping applications. Weibull distribution was used to model the monthly mean wind speed for a location in a rural area of Ngaoundere. It has been found that the Weibull distribution can be used to provide accurate estimation of the mean wind speed. The mean electric power and energy was computed based on the Vestas V25 and V100 power curves. Taking into account the wind regime characteristics of our site, we have provided the amount of water which can be expected from each type of wind pumps. From the results, it is clear that electric pump offers better performances than piston and rotodynamic pumps. Furthermore, if storage devices like batteries are combined to the system, water could be pumped at any time of the day independently of the wind availability. These systems could be very useful for people living in rural areas far from urban cities.

Increased chlorophyll-a concentration in the South China Sea caused by occasional sea surface temperature fronts at peripheries of eddies

ABSTRACTThis study investigates the processes of occasional sea surface temperature (SST) fronts and their impacts on chlorophyll-a concentration (chl-a) in the South China Sea (SCS), based on satellite remote sensing and in situ observations in 2009–2013. The SST fronts were detected by an entropy-based edge detection algorithm method from satellite-derived SST images with a 0.011° grid size. Three offshore SST front case studies (S1, S2 and S3) at the peripheries of eddies in the northern SCS were studied. In case S1 in September 2013, two SST fronts were detected with gradient magnitudes (GMs) greater than 0.06°C km–1 in the cyclonic eddy and 0.08°C km–1 in the periphery waters, and the fronts only existed for one and two days, respectively. After three and seven days, the high chl-a was found in the strong SST front waters which were about 51 and 54% higher than the concentration in the surrounding waters. The depth of the maximum chl-a elevated from the subsurface (50 m) to the surface. In case S2 in August 2013, two SST fronts were detected at the periphery of an anti-cyclonic eddy with GM stronger than 0.06°C km–1 and only existed for one day. After two days, the chl-a in the SST front waters was about 40% higher than the levels in the surrounding waters. In case S3 in June 2009, the GM of the eddy-feature SST front was stronger than 0.12°C km–1 and existed for three days, which was generated by tropical cyclone Linfa. The chl-a in the eddy-feature phytoplankton bloom was 6 times higher than in the surrounding waters. The results show that, in general, occasional offshore SST fronts at peripheries of eddies have stronger influence on surface chl-a, comparing to those seasonal coastal and permanent offshore SST fronts, via ‘Wind Pump’ effects.

Case Study of the Wind Potential and Its Utilisation for Water Pumping

Renewable energy resources (solar, wind and biomass) is one of the most fundamental of natural resources that Sudan must harness in its efforts for rapid economic development. The role of renewable energy technologies in the development process cannot be over – emphasised. The demand for energy in Sudan has increased tremendously over the years and will continue to increase in view of the accelerating pace of population growth, urbanisation and industrialisation. Comprehensive renewable energy resources management is a necessity. Human resource development should be based on education and training programs funded both by the private and public sector. Promotion research and development, demonstration and adaptation of energy resources amongst national, regional, and international organisations which seek clean, pure, safe, and abundant energy sources. Results, suggest that, wind pumps, solar stills, and biogas energy must be encourage, invested, and implemented, but especially for remote rural areas of Sudan.

Ground surface temperature and humidity, ground temperature cycles and the ice table depths in University Valley, McMurdo Dry Valleys of Antarctica

AbstractIn the upper McMurdo Dry Valleys, 90% of the measured ice table depths range from 0 to 80 cm; however, numerical models predict that the ice table is not in equilibrium with current climate conditions and should be deeper than measured. This study explored the effects of boundary conditions (air versus ground surface temperature and humidity), ground temperature cycles, and their diminishing amplitude with depth and advective flows (Darcy flow and wind pumping) on water vapor fluxes in soils and ice table depths using the REGO vapor diffusion model. We conducted a series of numerical experiments that illustrated different hypothetical scenarios and estimated the water vapor flux and ice table depth using the conditions in University Valley, a small high elevation valley. In situ measurements showed that while the mean annual ground surface temperature approximates that in the air, the mean annual ground surface relative humidity (>85%ice) was significantly higher than in the atmosphere (~50%ice). When ground surface temperature and humidity were used as boundary conditions, along with damping diurnal and annual temperature cycles within the sandy soil, REGO predicted that measured ice table depths in the valley were in equilibrium with contemporary conditions. Based on model results, a dry soil column can become saturated with ice within centuries. Overall, the results from the new soil data and modeling have implications regarding the factors and boundary conditions that affect the stability of ground ice in cold and hyperarid regions where liquid water is rare.

Design and Simulation of Wind Pump System for Ban Village

Design and Simulation of Wind Pump System for Ban Village

Assessing Performance of Small‐Scale Pumped Irrigation Systems in sub‐Saharan Africa: Evidence from a Systematic Review

AbstractSmall‐scale irrigation (SSI) has significant potential to increase crop productivity in sub‐Saharan Africa (SSA). Pumped irrigation systems are one of the technologies increasingly being used by smallholder farmers. The aim of this study was to systematically review evidence on the performance of SSI pumped systems, including motorized, treadle, rope and washer, solar and wind pumps. The study revealed a lack of standardization and use of a wide range of indicators to assess performance. Most evidence related to motorized pumps, and these studies confirmed mixed levels of performance; studies relating to other types of pumped system mostly reported a positive impact, although the method of assessment used was critical. Studies reporting positive impacts tended to be those that used socio‐economic based factors such as yield and profitability, whereas studies reporting mixed performance tended to be those that relied more on technically based indicators such as pumping and irrigation system efficiency. The analysis highlights the sensitivity of interpreting findings from different studies, and how caution should be exercised when comparing performance within and between different types of irrigation systems. The implications for supporting policy development and identifying future research gaps are discussed. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Wind energy development: Innovation and new prospective

The imminent exhaustion of fossil energy resources and the increasing demand for energy were the motives for those reasonable in world to put into practice an energy policy based on rational use of energy; and on exploitation of new and renewable energy sources. After 1980, as the supply of conventional energy has not been able to follow the tremendous increase of the production demand in rural areas of the world, a renewed interest for the application of solar and wind energy has shown in many places. Therefore, the researchers and engineers began to pay more attention to wind and solar energy utilisation in rural areas. Because the wind energy resource in many rural areas is sufficient for attractive application of wind pumps, and as fuel is insufficient, the wind pumps will be spread on a rather large-scale in the near future. Wind is a form of renewable energy, which is always in a non-steady state due to the wide temporal and spatial variations of wind velocity. The need for the provision of new data stations in order to enable a complete and reliable assessment of the overall wind power potential of the country is to be identified and specific locations suggested. This article presents the background and ideas of the development of the concept as well as the main results and experience gained during ongoing projects up to now. In the world, various designs of wind machines for water pumping have been developed and some designs are presently manufactured commercially. Results suggest that wind power would be more profitably used for local and small-scale applications especially for remote rural areas. It is concluded that many parts of the world is enjoyed with abundant wind and solar energy resources.

Feasibility Evaluation of the Wind Energy as an Alternative Energy Source for the Irrigation of Greenhouse Crops

Wind energy is evaluated as an alternative energy source for the irrigation of greenhouse crops at four different locations in Asia; Shouguang (China), Sargodha (Pakistan), Buan and Gimhae (South Korea). We studied potential of the wind resources available at each location for the use of a wind pump, to meet tomato crop (same for all locations) annual water demand. Daily and monthly evapotranspiration of the crop under different greenhouse sizes and volume of water pumped by using wind pump are determined for the water budgeting and economic analysis of the system. The concept of Levelized cost of energy (LCOE) in US dollar (US$) is used for the economic assessment, and we compare LCOE of wind pump and other sources (solar photovoltaic pump, diesel pump, electricity from the grid) of water pumping being used for the irrigation purpose. The initial results indicate that the LCOE associated with diesel-powered pumps and electricity from the grid is low. However, in the case of Shouguang and Buan have not received conventional energy source yet and have adequate wind resources to fulfill the irrigation requirement of the large area. The average wind resources in Sargodha and Gimhae are found inadequate for the large area water pumping, but irrigation of medium size greenhouse could be doable. Wind pumping system’s internal rate of return found at each location, Gimhae, Buan, Shouguang and Sargodha are 4.4 %, 10.0 %, 5.2 % and below 1.0 % respectively.

Performance of Wind Pump Prototype

A wind pump prototype with 3.6 m rotor diameter, 19 m hub height above ground and 0.22 mm reciprocating pump stroke has been developed at the Department of Mechanical Engineering, Mekelle University. The prototype was designed and manufactured locally. Theoretical model based on combined efficiency of the rotor and the reciprocating pump was used to estimate the performance of the wind pump. One year wind speed data collected at 10 m height was extrapolated to the wind pump hub height using wind shear coefficient. The model assumed balanced rotor power and reciprocating pump, hence did not consider the effect of pump size. The theoretical model estimated the average daily discharge to be around 50 m 3 and 30 m 3 at 8 m and 12 m head, respectively. The prototype was tested with the same pump stroke but two different size pumps at two different heads. The pumps were with internal diameter of 55 and 70 mm and the test heads were at 8 and 12 m. Measurement of the flow rate, rotational speed and wind speed were made every 10 minutes during the test period. The data collected were analyzed to find the performance of the wind pump at the two test heads and two pump sizes. The flow rate data was plotted against binned wind speed data to determine the linear fit function. The linear fit function was then used to estimate the flow rate at any wind speed. With the 55 mm pump the measured average daily discharge was 20 and 19 m 3 at 8 m and 12 m head, respectively. With the 70 mm pump the measured average daily discharge was 41 m 3 and 30 m 3 at 8 m and 12 m head, respectively. Keywords : Wind pump, Windmill, Performance testing, Pump efficiency, Pump discharge, Ethiopia.

Dynamics of ozone and nitrogen oxides at Summit, Greenland: I. Multi-year observations in the snowpack

Abstract A multi-year investigation of ozone (O 3 ) and nitrogen oxides (NO x ) in snowpack interstitial air down to a depth of 2.8 m was conducted at Summit, Greenland, to elucidate mechanisms controlling the production and destruction of these important trace gases within the snow. Snowpack O 3 values ranged from 30 to 40 ppbv during winter months, and dropped below 10 ppbv in summer. Wintertime NO x levels were low at all depths in the snowpack (below 10 pptv for NO and below 25 pptv for NO 2 ). In the summer, NO values up to 120 pptv, and NO 2 mixing ratios up to ∼700 pptv were observed. O 3 loss within the snowpack was observed throughout all seasons. The magnitude of the O 3 loss rate tracked the seasonal and diurnal cycle of incoming short wave solar radiation. Production of NO within a shallow layer of the snowpack was recorded during the spring and summer months. NO 2 production also occurred, and heightened levels were measured down to 2.5 m in the snowpack. The average daily maximum in NO was observed at solar noon, and the minimum was seen during night. The daily peak in NO 2 was on average 7 h shifted from the incoming solar radiation and NO maxima. NO x levels in interstitial air during spring were enhanced relative to summer and fall. The influence of meteorological effects such as wind pumping on snowpack interstitial air levels of O 3 and NO x was investigated using case study periods. Increased snowpack ventilation during high wind events was found to yield enhancement in snowpack NO x , with this effect being enhanced during times when O 3 was elevated in ambient air. This behavior suggests that O 3 is involved in NO x production in the snowpack. This extensive set of observations is used to re-evaluate physical and chemical processes that describe the dynamic O 3 and NO x chemistry occurring within snowpack interstitial air at Summit.

Farmers’ Comparative Use Assessment Of Wind And Electric Pump For Irrigation

Abstract Keta District provides one of the best wind regimes in Ghana and farming is the main occupation of most people in the communities of the district, notably the anloga community. A small size wind pump (1.6m rotor diameter) is currently in operation in Anloga in the Keta District on pilot bases to verify its cost effectiveness compared with the hydro electric power technology. The high electricity tariff paid every month for power consumption deterred majority of the farmers using hydro electricity technology for pumping. A survey conducted revealed that out of about 50 farmers, only 29% engaged in the use of electric power for pumping whilst 69% still use the manual method. 2% of the farmers are using wind energy technology on pilot bases. Farmers in these coastal communities may have engaged in the use of wind energy for water pumping but for its high initial cost.

Feasibility study of a wind powered water pumping system for rural Ethiopia

Water is the primary source of life for mankind and one of the most basic necessities for rural development. Most of the rural areas of Ethiopia do not have access to potable water. Is some regions of the country access potable water is available through use of manual pumping and Diesel engine. In this research, wind water pump is designed to supply drinking water for three selected rural locations in Ethiopia. The design results show that a 5.7 m diameter windmill is required for pumping water from borehole through a total head of 75, 66 and 44 m for Siyadberand Wayu, Adami Tulu and East Enderta to meet the daily water demand of 10, 12 and 15 m 3 , respectively. The simulation for performance of the selected wind pump is conducted using MATLAB software and the result showed that monthly water discharge is proportional to the monthly average wind speed at the peak monthly discharge of 685 m 3 in June, 888 m 3 in May and 1203 m 3 in March for Siyadberand Wayu, Adami Tulu and East Enderta sites, respectively. An economic comparison is conducted, using life cycle cost analysis, for wind mill and Diesel water pumping systems and the results show that windmill water pumping systems are more feasible than Diesel based systems.

Potential of Wind Energy Development for Water Pumping in Ngaoundere

The modelling of wind energy conversion systems is of great importance if one intends to develop water pumping applications for a sustainable development. This paper presents a technical assessment based on the measured wind data in which we investigate the possibility of coupling piston pump, roto-dynamic pump and electric pump with wind rotors for water pumping applications. Weibull distribution is used to model the monthly mean wind speed for a location in the town of Ngaoundere. It is found that there is a good agreement between the predicted values of the mean wind speed and those obtained from data suggesting that the Weibull distribution can be used to provide accurate estimation of the mean wind speed. The mean electric power and energy are computed based on the power curves of Vestas V25 and V100. Taking into account the wind regime characteristics of our site, we provide the amount of water which can be expected from each type of wind pumps. The monthly amount of water has minimum and maximum average values of 422 m3 and 674 m3 for the piston pump, 1275 m3 and 1982 m3 for the roto-dynamic pump and 31334 m3 and 100042 m3 for the electric pump. From the results, it is clear that electric pump offer better performances than piston and rotodynamic pumps.

Wind pumps for irrigating greenhouse crops: Comparison in different socio-economical frameworks

A simple methodology was used to compare the economic feasibility of wind pump technology, solar photovoltaic pumping, diesel generators, and connection to the electrical grid to provide energy for pumping irrigation water in commercial greenhouses in Spain, Cuba and Pakistan (countries with different developmental backgrounds). The analysis took into account wind resources, distance to the grid, water storage tank volume requirements, and planting dates. Comparisons were made in terms of the levelised cost of energy associated with each system. For all three countries, if a grid connection was already in place, installing wind pumps would be economically unwise. Where no grid connection exists, the distance to the grid and the wind resource available are key factors to be taken into consideration when deciding between options: a 10% increase in the average wind speed is equivalent to a 20% reduction in the distance to the grid in terms of costs return. Finally, the water elevation has a major influence on the economic feasibility of wind pump technology, much more than, for example, on solar photovoltaic pumping technology. The results reveal that, generally, the critical factors to consider when making energy management decisions differ depending between countries. In Spain, the proximity of the electrical grid makes the connection to it the best option. In Pakistan, scarce wind resources are a serious limiting factor. Cuba, however, has good wind resources; water elevation, distance to the grid and water storage needed are the critical factors when determining the economic feasibility of wind pumping there.

Stochastic Analysis of Wind Energy for Wind Pump Irrigation in Coastal Andhra Pradesh, India

The rapid escalation in the prices of oil and gas as well as increasing demand for energy has attracted the attention of scientists and researchers to explore the possibility of generating and utilizing the alternative and renewable sources of wind energy in the long coastal belt of India with considerable wind energy resources. A detailed analysis of wind potential is a prerequisite to harvest the wind energy resources efficiently. Keeping this in view, the present study was undertaken to analyze the wind energy potential to assess feasibility of the wind-pump operated irrigation system in the coastal region of Andhra Pradesh, India, where high ground water table conditions are available. The stochastic analysis of wind speed data were tested to fit a probability distribution, which describes the wind energy potential in the region. The normal and Weibull probability distributions were tested; and on the basis of Chi square test, the Weibull distribution gave better results. Hence, it was concluded that the Weibull probability distribution may be used to stochastically describe the annual wind speed data of coastal Andhra Pradesh with better accuracy. The size as well as the complete irrigation system with mass curve analysis was determined to satisfy various daily irrigation demands at different risk levels.

Continuous measurement of CO2 flux through the snowpack in a dwarf bamboo ecosystem on Rishiri Island, Hokkaido, Japan

To investigate the dynamics and environmental drivers of CO2 flux through the winter snowpack in a dwarf bamboo ecosystem (Hokkaido, northeast Japan), we constructed an automated sampling system to measured CO2 concentrations at five different levels in the snowpack, from the base to the upper snow surface. Using a gas diffusion approach, we estimated an average apparent soil CO2 flux of 0.26 μmol m−2 s−1 during the snow season (December–April); temporally, the CO2 flux increased until mid-snow season, but showed no clear trend thereafter; late-season snow-melting events resulted in rapid decreases in apparent CO2 flux values. Air temperature and subnivean CO2 flux exhibited a positive linear relationship. After eliminating the effects of wind pumping, we estimated the actual soil CO2 flux (0.41 μmol m−2 s−1) to be 54% larger than the apparent flux. This study provides new constraints on snow-season carbon emissions in a dwarf bamboo ecosystem in northeast Asia.

Electrohydrodynamic Microfabricated Ionic Wind Pumps for Thermal Management Applications

This work demonstrates an innovative microfabricated air-cooling technology that employs an electrohydrodynamic (EHD) corona discharge (i.e., ionic wind pump) for electronics cooling applications. A single, microfabricated ionic wind pump element consists of two parallel collecting electrodes between which a single emitting tip is positioned. A grid structure on the collector electrodes can enhance the overall heat-transfer coefficient and facilitate an IC compatible batch process. The optimized devices studied exhibit an overall device area of 5.4 mm × 3.6 mm, an emitter-to-collector gap of ∼0.5 mm, and an emitter curvature radius of ∼12.5 μm. The manufacturing process developed for the device uses glass wafers, a single mask-based photolithography process, and a low-cost copper-based electroplating process. Various design configurations were explored and modeled computationally to investigate their influence on the cooling phenomenon. The single devices provide a high heat-transfer coefficient of up to ∼3200 W/m2 K and a coefficient of performance (COP) of up to ∼47. The COP was obtained by dividing the heat removal enhancement, ΔQ by the power consumed by the ionic wind pump device. A maximum applied voltage of 1.9 kV, which is equivalent to approximately 38 mW of power input, is required for operation, which is significantly lower than the power required for the previously reported devices. Furthermore, the microfabricated single device exhibits a flexible and small form factor, no noise generation, high efficiency, large heat removal over a small dimension and at low power, and high reliability (no moving parts); these are characteristics required by the semiconductor industry for next generation thermal management solutions.

DEVELOPMENT OF ARCHIMEDEAN’S PIPE-SCREW FOR THAI SAIL WINDPUMP

This study describes new considerations in the desi gn and development of Archimedean’s Pipe-Screw especially for water pumping in case of low head hi gh volume form open farm pond at Rajamangala University of Technology Rattanakosin, Thailand. The objectives of this research is to develop an Archimedean’s Pipe-Screw especially for water pumping in case of low head high volume form open farm pond used for water pumping with Thai sail windmill, at any location of low wind speed of Thailand and tests the performance of an Archimedean’s Pipe-Scre w Model (APSM). The experimental was carried out on diameter of Archimedean’s Pipe-Screw is φ5/8”, the pitch Archimedean’s Pipe-Screw (P) is 0.6 , 0.8, 1.0, 1.2, 1.4, 1.6, 1.8 and 2.0 D for angle slope of the screw with the horizontal ( α) is 20, 25, 30°C in laboratory scale Archimedean’s Pipe-Screw model. Archimedean’s Pipe-Screw tests were conducted to assess the performance of characteristics of Archimedean’s Pip e-Screw model. A model of pump has been manufactured; 1.0 m long with the blade small rubbe r tube was constructed. The output of the experimen ts recommenced for development the prototype of Archimedean’s Pipe-Screw for the Thai sail wind pump. The prototype of pump has been manufactured, 4.0 m long, 8 m diameter. This wind pump has twelve triangular sails sweeping a circle of 8 m diameter. For the construction of this Archimedean’s Pipe-Sc rew wind pump all efforts were made to use maximize materials and local parts available in the market for large scale of Archimedean’s screw-pipe for Thai sail win d pump. The cost of material and parts is 145,000 B aht excluding the cost of machining and fabrication. Wa ter discharge was in the range 0.005-0.081 lps. It can be seen maximum water discharge of pitch Archimedean’s Pipe-Screw (P) is 1.4D at 80 rpm for α = 20° was 0.081 lps. For the result of prototype of Archimede an’s Pipe-Screw for Thai sail wind pump, it was fou nd that the curves for the prototype of Thai sail wind mill coupled to twelve Archimedean’s Pipe-Screw pump of wind speed and the discharge of was increased de pending on wind speed. The discharge amount varied between 9.56-38.23 m 3 /h at head of 1.5 m in wind speeds from 1.0-5.0 m s -1 that the overall efficiency of this windmill for water pumping was highest (76.96%) at wind speed of 1.4 m s -1 .